Successful management of maternal anti-PP1P k alloimmunization in pregnancy with therapeutic plasma exchange and intravenous immunoglobulin

• Published in: Journal of clinical apheresis 2024-06, Vol.39 (3), p.e22120
• Main Authors: Hadjiyannis, Yannis, Jones, Jennifer M, Chibisov, Irina, Kiss, Joseph, Gabert, Kim, Sevcik, Joan, Bakdash, Suzanne, Binstock, Anna, Kilonsky, Carolyn, Parviainen, Kristiina, Kaplan, Alesia
• Format: Article
• Language: English
• Subjects: Adult; Erythroblastosis, Fetal - prevention & control; Erythroblastosis, Fetal - therapy; Female; Humans; Immunoglobulins, Intravenous - therapeutic use; Infant, Newborn; Isoantibodies - blood; Isoantibodies - immunology; Plasma Exchange - methods; Pregnancy; Young Adult
• ISSN: 0733-2459; 1098-1101
• DOI: 10.1002/jca.22120

Anti-PP1P alloimmunization is rare given ubiquitous P1PK expression. Prevention of recurrent miscarriages and hemolytic disease of the fetus and newborn (HDFN) in pregnant individuals with anti-PP1P antibodies has relied upon individual reports. Here, we demonstrate the successful management of maternal anti-PP1P alloimmunization in a 23-year-old, G2P0010, with therapeutic plasma exchange (TPE), intravenous immunoglobulin (IVIG), and monitoring of anti-PP1P titers. Twice-weekly TPE (1.5 plasma volume [PV], 5% albumin replacement) with weekly titers and IVIG (1 g/kg) was initiated at 9 weeks of gestation (WG). The threshold titer was ≥16. Weekly middle cerebral artery-peak systolic velocities (MCA-PSV) for fetal anemia monitoring was initiated at 16 WG. PVs were adjusted throughout pregnancy based on treatment schedule, titers, and available albumin. Antigen-negative, ABO-compatible RBCs were obtained through the rare donor program and directed donation. An autologous blood autotransfusion system was reserved for delivery. Titers decreased from 128 to 8 by 10 WG. MCA-PSV remained stable. At 24 WG, TPE decreased to once weekly. After titers increased to 32, twice-weekly TPE resumed at 27 WG. Induction of labor was scheduled at 38 WG. Vaginal delivery of a 2950 g neonate (APGAR score: 9, 9) occurred without complication (Cord blood: 1+ IgG DAT; Anti-PP1P eluted). Newborn hemoglobin and bilirubin were unremarkable. Discharge occurred postpartum day 2. Anti-PP1P alloimmunization is rare but associated with recurrent miscarriages and HDFN. With multidisciplinary care, a successful pregnancy is possible with IVIG and TPE adjusted to PV and titers. We also propose a patient registry and comprehensive management plan.